The reaction of $(en)Pd(NO_3)_2$ (en = ethylenediamine) with 1,4-bis(dimethyl-4-pyridylsilyl)benzene (L) affords cyclodimer, $[(en)Pd(L)]_2(NO_3)_4$, whereas the reaction of $(tmeda)Pd(NO_3)_2$ (tmeda = N,N,N’,N’-tetramethylethylenediamine) with L gives cyclotrimer, $[(tmeda)Pd(L)]_3(NO_3)_6$. Both complexes exist as catenane in water. The catenated cyclodimer is rigid whereas the catenated cyclotrimer is dynamic in water. The catenated cyclotrimers afford hydrogel containing 98.5% water below 2 ${^{circ}C}$. The hydrogel changes to its sol around 38 ${^{circ}C}$, and to its clear solution at 78 ${^{circ}C}$. Such a notable difference between $[(en)Pd(L)]_2(NO_3)_4$ and $[(tmeda)Pd(L)]_3(NO_3)_6$ might be explained by their different dynamic behavior via ring size effects.